The aim of this study was to investigate whether GABA(A) and/or GABA(B) receptor-mediated mechanisms contribute to the impaired ventilatory response and reduced maximal aerobic exercise capacity in obese Zucker rats. Ten lean and 10 obese Zucker rats were studied at 12 wk of age. Minute ventilation (Ve), tidal volume (Vt), and breathing frequency (f) during room air breathing and in response to...

BACKGROUND/AIMS AND METHODS gamma-Aminobutyric acid (GABA) is localized in epithelial cells and intrinsic nerve fibers of the gastric mucosa raising the possibility of a regulatory role for this transmitter. Therefore, it was the aim of the present study to examine the effect of exogenous and endogenous GABA on the neuroendocrine functions of the isolated perfused rat stomach. RESULTS Infusio...

In the inferior colliculus (IC) of the big brown bat, a subpopulation of cells ( approximately 35%) are tuned to a narrow range of sound durations. Band-pass tuning for sound duration has not been seen at lower levels of the auditory pathway. Previous work suggests that it arises at the IC through the interaction of sound-evoked, temporally offset, excitatory and inhibitory inputs. To test this...

The current model of basal ganglia organization postulates the existence of a functional partitioning into sensorimotor, associative and limbic territories, implicated in motor, cognitive and emotional aspects of behaviour, respectively. This organization was proposed initially on the basis of the cortico-striatal projections and was extended to the various structures of the basal ganglia. Whil...

Discrimination of amplitude and frequency modulated sounds is an important task of auditory processing. Experiments have shown that tuning of neurons to sinusoidally frequency- and amplitude-modulated (SFM and SAM, respectively) sounds becomes successively narrower going from lower to higher auditory brain stem nuclei. In the inferior colliculus (IC), many neurons are sharply tuned to the modul...

Single-unit recordings were made in the intact anesthetized rat of the responses of dorsal horn neurons to C-, Adelta-, and Abeta-fiber stimulation. The postdischarge and windup responses of the same cells along with responses to innocuous stimuli, prod and brush, also were measured. The effects of (-)-bicuculline-methobromide (0.5, 5, 50, and 250 microg) were observed on these neuronal respons...

In this paper it has been shown that deterioration of the brain cortex capillary system and negative dynamics of cerebral tissue morphology occur under conditions of hypo kinesia. Simultaneously, gamma-aminobutyric acid (GABA) and piracetam have been shown to favor the development of vasodilation and prevent further worsening of the cerebral blood supply. During the experiment, it was also ...

Orientation selectivity is an important emergent property of neurons in the primary visual cortex, and inhibition is thought to play an important role in establishing this selectivity. But the relationship between strength of inhibition and orientation selectivity is unclear. To investigate this relationship, we electrophoretically applied the inhibitory transmitter GABA and the GABA(A) antagon...

The current study examined the effects of systemic administration of a GABA agonist [midazolam (MDZ)] and a GABA antagonist (bicuculline) on fear responding after brief CS exposure, a procedure thought to involve memory reconsolidation. Using a contextual fear-conditioning paradigm, rats were initially given two context-shock training trials, followed 24 hrs later by a 90-s context exposure (re...